In order to support transmissions of different services such as audio data or video data towards different recipients residing in e.g. different countries, efficient communication networks are necessary. An efficient horizontally layered architecture is e.g. described in “Control Servers in the Core Network”, Ericsson Review No. 4, 2000. By way of example, the layered network architecture as e.g. introduced with release for of the 3GPP (3rd Generation Partnership Project) specification comprises three distinct layers: an application layer, a network control layer and a connectivity layer. The application layer supports end-user applications and may be implemented in mobile stations or application servers in the network. The application layer may interface with the network layer via a set of application program interfaces (API) which enables designing and implementing different services and applications. The network control layer supports communicating services across e.g. different types of networks such as circuit-switched domain networks based on the GSM standard using e.g. an ISDN-related technology or packet-switched networks employing e.g. the GPRS technology. The connectivity layer is a transport layer capable of transporting any type of service via e.g. voice, data and multimedia streams.
According to the UMTS (Universal Mobile Telecommunications System) technology, the control layer may comprise a mobile switching center (MSC) handling control layer functions at an interface between an access network and a core network. The communication between the access network and the MSC server may be performed upon the basis of RANAP messages (Radio Access Network Application Protocol). The network control layer according to the UMTS technology may further comprise a transit switching center (TSC) managing communications between the core network and another network such as e.g. ISDN (Integrated Services Digital Network) or PSTN (Public Switched Telephone Network) network. The MSC and the TSC may communicate via gateway control protocol (GCP) messages with a respective media gateway (MGW) or mobile MGW (M-MGW) arranged in the connectivity layer for managing data transmissions. Typically, a MGW receives data from a communication entity, such as a mobile station or an application server, via the access network and e.g. converts the ATM (Asynchronous Transfer Mode) data streams into IP (Internet Protocol) data streams for further transport.
Another emerging communication technology for delivering multimedia services across fixed and mobile access networks is provided by the IP Multimedia Subsystem (IMS) technology. The network architecture according to IMS comprises a service layer corresponding to the aforementioned application layer, a control and connectivity layer corresponding to the aforementioned network control layer and an access layer corresponding to the aforementioned connectivity layer. In particular, the control and connectivity layer may comprise call session control functions (CSCF) forming central entities for the provision of the SIP signalling (SIP: Session Initiation Protocol). The control and connectivity layer further comprises a MGCF (Media Gateway Control Function) communicating with the CSCF via SIP messages and with media gateways arranged within the access layer using media gateway messages according to e.g. the H.248 protocol. The control and connectivity layer may further comprise a MRF (Media Resource Function) providing media services e.g. in a home network.
A further emerging communication technology is the Evolved Packet System (EPS) as defined by the 3GPP standards organization. One of the communication technologies deployed within the context of the EPS is the LTE access technology (LTE: Long Term Evolution). The EPS comprises a MME (Mobility Management Entity) forming a control-entity suitable for signalling and selecting a serving gateway (SGW) which routes and forwards user data packets is provided. The MME and the SGW are parts of an Evolved Packet Core (EPC) which comprises further elements such as SGSN (Serving GPRS Support Entity) or PGW (Packet Data Network Gateway).
With exemplary reference to the afore-mentioned communication technologies, a number of network entities may handle a significant number of user communication signals relating to a user and, respectively, comprising payload and signalling load. However, some of these network entities are mainly affected by signalling load and signalling-load-related procedures, while other entities are mainly concerned with payload and payload—related procedures. Therefore, the available network resources may be not efficiently exploited when e.g. a network entity mainly handling signalling load also is provided with a capability of handling payload.